Hi and welcome!
What bike is it?
Is your commute mainly on-street with traffic?
You could just do it and change and tweak your ways as you go but a little preparation won't hurt and may make the experience all that more enjoyable.
10 miles one way for someone who didn't ride for a while can be a lot to handle in the beginning. Even if you are in a good shape you will hurt first few times. So you may ride a bit first to see how much you can handle and get your muscles used to the new type of workout.
Make sure your bike is set up properly, everything works well ("new" doesn't mean "working well"), get your riding position dialed in properly.
Ride your commute route on a day-off to check it out.
Think about logistics: what you need to carry, how to change your clothes at work, where to park your bike.
Get fenders, you don't want to get splashed with dog poo and urine, vomit, dead squirrel blood, chemicals.... you get the picture. Fenders are not just for wet weather, you know.
Get puncture resistant tires. You will be sooo happy that you did
Get a rear rack and rack bag or panniers, unless you don't mind carrying a backpack. Although, a 10 mile ride will be much more pleasant without any weight on your back. Waterproof panniers are really nice for commuting.
If you ride with traffic think about your visibility: reflective elements, bright clothing.
Get lights if riding in the dark. Although, powerful blinkers are good during the day too if the weather is bad (see visibility above).
Helmet: that's up to you. I like it. I had close encounters with slippery pavement a couple of times in winter and a helmet proved its worth for me
Carry spare tubes (2 is a good number), a pump and a set of tools needed to replace a tube. Patching is best done later at home, so keep the punctured tubes and patch them later. It's a waste of time en route and you're more like to do a lousy job on the road. Practice taking your wheels off and replacing the tubes. You don't want to do this the first time at 6am on a rainy day. If you don't carry spare tubes and tools your puncture resistant tires will get punctured, Murphy's law.
Commuting is about getting you to and from work safely, in style (if you want), efficiently an about being fun and a workout too; being green, saving the planet, being anti-oil, etc are secondary. Make it as much fun as you can. It shouldn't be hard and miserable or you won't want to do it any more. Don't do anything for show, you're doing this for yourself, it'll eventually become a lifestyle and you may even find yourself riding your bike for more reasons. I have a car but I often ride my bike for errands that don't require carrying heavy loads. It's fun, no need to worry about parking (I live in New York) and in some cases it's faster!
Stay alive. Don't try to prove anything. Don't look for fights with drivers. Avoid confrontations. People behind the wheel tend to be um... you know, less friendly so to speak, and you won't win by enraging them. Road rage is a real phenomenon and you don't want to be the target.
If possible, avoid trouble traffic spots, metal-surface bridges, roads with really bad pavement, really bad railroad crossings, etc. Detour around them if necessary. Your route doesn't need to be the shortest one, but the safest one and one that's fun to ride. A detour may cost you 5 minutes at most versus becoming news in your local paper.
I often detour to go through a park or, on the way home, to ride longer if the weather is nice. I followed my own advice as stated above for several years and I had no accidents, I never got seriously hurt (not counting those few bumps on my head and bruises on my side from slamming the pavement). I had few arguments with drivers, but everyone has a bad day now and then
Although, it's not really as bad as I might have made it sound: just be aware of your surroundings, be defensive, use your head and you'll be fine.
Read these forums!!!
And.... don't ride the wrong way! That's bad juju and other cyclists will curse you to no end! Not to mention you will end up causing accident pretty quickly.
Adam